Tags

Joomla included built-in support for tags in April 2013, with the release of Joomla 3.1. Key features are:

• Multilanguage.
• Nested tags structure.
• Integrated in all the core content (using the first Unified Content Model approach seen in the core).
• Selectable tag field mode (AJAX or nested).
• On the fly tag creation.
• Easily integration in any extension.

Usage

Joomla tags can be used to search and display content. Tags can be created on-the-fly, or pre-defined. The default tag field behavior can be set in the global com_tags settings.

Tag field

Extensions can define a tag field in the XML file:

<field name="tags" type="tag"
    label="JTAG" description="JTAG_DESC"
    class="inputbox span12 small" multiple="true"
/>

Joomla will automatically include any dependencies required.

Usefull links

Introduction to the Tag Field - http://magazine.joomla.org/issues/issue-apr-2103/item/1225-joomla-tag-field

The New Tags Feature - https://www.ostraining.com/blog/joomla/joomla-31-tags/